/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.hop.pipeline.transforms.fileexists;

import org.apache.commons.vfs2.FileType;
import org.apache.hop.core.ResultFile;
import org.apache.hop.core.exception.HopException;
import org.apache.hop.core.row.RowDataUtil;
import org.apache.hop.core.util.Utils;
import org.apache.hop.core.vfs.HopVfs;
import org.apache.hop.i18n.BaseMessages;
import org.apache.hop.pipeline.Pipeline;
import org.apache.hop.pipeline.PipelineMeta;
import org.apache.hop.pipeline.transform.BaseTransform;
import org.apache.hop.pipeline.transform.ITransform;
import org.apache.hop.pipeline.transform.TransformMeta;

/** Check if a file exists* */
public class FileExists extends BaseTransform<FileExistsMeta, FileExistsData>
    implements ITransform<FileExistsMeta, FileExistsData> {

  private static final Class<?> PKG = FileExistsMeta.class; // For Translator

  public FileExists(
      TransformMeta transformMeta,
      FileExistsMeta meta,
      FileExistsData data,
      int copyNr,
      PipelineMeta pipelineMeta,
      Pipeline pipeline) {
    super(transformMeta, meta, data, copyNr, pipelineMeta, pipeline);
  }

  @Override
  public boolean processRow() throws HopException {

    boolean sendToErrorRow = false;
    String errorMessage = null;

    Object[] r = getRow(); // Get row from input rowset & set row busy!
    if (r == null) { // no more input to be expected...

      setOutputDone();
      return false;
    }

    boolean fileexists = false;
    String filetype = null;

    try {
      if (first) {
        first = false;
        // get the RowMeta
        data.previousRowMeta = getInputRowMeta().clone();
        data.NrPrevFields = data.previousRowMeta.size();
        data.outputRowMeta = data.previousRowMeta;
        meta.getFields(data.outputRowMeta, getTransformName(), null, null, this, metadataProvider);

        // Check is tablename field is provided
        if (Utils.isEmpty(meta.getFilenamefield())) {
          logError(BaseMessages.getString(PKG, "FileExists.Error.FilenameFieldMissing"));
          throw new HopException(
              BaseMessages.getString(PKG, "FileExists.Error.FilenameFieldMissing"));
        }

        // cache the position of the field
        if (data.indexOfFileename < 0) {
          data.indexOfFileename = data.previousRowMeta.indexOfValue(meta.getFilenamefield());
          if (data.indexOfFileename < 0) {
            // The field is unreachable !
            logError(
                BaseMessages.getString(PKG, "FileExists.Exception.CouldnotFindField")
                    + "["
                    + meta.getFilenamefield()
                    + "]");
            throw new HopException(
                BaseMessages.getString(
                    PKG, "FileExists.Exception.CouldnotFindField", meta.getFilenamefield()));
          }
        }
      } // End If first

      Object[] outputRow = RowDataUtil.allocateRowData(data.outputRowMeta.size());
      for (int i = 0; i < data.NrPrevFields; i++) {
        outputRow[i] = r[i];
      }
      // get filename
      String filename = data.previousRowMeta.getString(r, data.indexOfFileename);
      if (!Utils.isEmpty(filename)) {
        data.file = HopVfs.getFileObject(filename);

        // Check if file
        fileexists = data.file.exists();

        // include file type?
        if (meta.isIncludefiletype() && fileexists && !Utils.isEmpty(meta.getFiletypefieldname())) {
          filetype = data.file.getType().toString();
        }

        // add filename to result filenames?
        if (meta.isAddresultfilenames() && fileexists && data.file.getType() == FileType.FILE) {
          // Add this to the result file names...
          ResultFile resultFile =
              new ResultFile(
                  ResultFile.FILE_TYPE_GENERAL,
                  data.file,
                  getPipelineMeta().getName(),
                  getTransformName());
          resultFile.setComment(BaseMessages.getString(PKG, "FileExists.Log.FileAddedResult"));
          addResultFile(resultFile);

          if (log.isDetailed()) {
            logDetailed(
                BaseMessages.getString(
                    PKG, "FileExists.Log.FilenameAddResult", data.file.toString()));
          }
        }
      }

      // Add result field to input stream
      outputRow[data.NrPrevFields] = fileexists;
      int rowIndex = data.NrPrevFields;
      rowIndex++;

      if (meta.isIncludefiletype() && !Utils.isEmpty(meta.getFiletypefieldname())) {
        outputRow[rowIndex] = filetype;
      }

      // add new values to the row.
      putRow(data.outputRowMeta, outputRow); // copy row to output rowset(s)

      if (log.isRowLevel()) {
        logRowlevel(
            BaseMessages.getString(
                PKG,
                "FileExists.LineNumber",
                getLinesRead() + " : " + getInputRowMeta().getString(r)));
      }
    } catch (Exception e) {
      if (getTransformMeta().isDoingErrorHandling()) {
        sendToErrorRow = true;
        errorMessage = e.toString();
      } else {
        logError(
            BaseMessages.getString(PKG, "FileExists.ErrorInTransformRunning") + e.getMessage());
        setErrors(1);
        stopAll();
        setOutputDone(); // signal end to receiver(s)
        return false;
      }
      if (sendToErrorRow) {
        // Simply add this row to the error row
        putError(getInputRowMeta(), r, 1, errorMessage, meta.getResultfieldname(), "FileExistsO01");
      }
    }

    return true;
  }

  @Override
  public boolean init() {
    if (super.init()) {
      if (Utils.isEmpty(meta.getResultfieldname())) {
        logError(BaseMessages.getString(PKG, "FileExists.Error.ResultFieldMissing"));
        return false;
      }
      return true;
    }
    return false;
  }

  @Override
  public void dispose() {
    if (data.file != null) {
      try {
        data.file.close();
        data.file = null;
      } catch (Exception e) {
        // Ignore close errors
      }
    }
    super.dispose();
  }
}
